Pump



March 2,5, 1930. D, D, LONG A 1,751,703

PUMP

Filed Nov. z, 1927 3 sheets-sheet 1 March 25, 1930. I D- LONG y t 1,751,703

PUMP

Filed Nomi. 192'.7 sv sheets-sheet 2 Dan/W 0. wfg

atto: 5114] March 255, 1930; l

D. D. LONG Dam'e/ D. orig` PUMP Filed Nov, 3, 1927 3 Sheets-Sheet 5 f7 6X 61' Z Sme/nto Patented Mar. 25, 1930 UNITED STATES PATENT OFFICE DANIEL D. LONG, o'F BoIsE, IDAHo, BY DEGREE or Drs'rmnnrioN '.ro MARTHA LONG,

or :BoIsE IDAHO PUMP Application led November 3, 1927. Serial Nro. 230,777.

The present invention relates to pumps and more especially to improvements in the construction and operation of that type of pump in which helical impellers or pistons are employed for conducting the supply to any suitable point of distribution.

One of the essential features of the invention is to provide a counter-balanced screw pump with a casing formed so as to materially reduce the friction of the liquid passing therethrough.

.A further object consists in drawing the liquid through the pump by means of parallel disposed impellers having double pitched interengaging threads arranged to provide a liquid tight seal for conducting the supply from the inlet to the outlet. Additionally, the ends of the threads have their-faces inclined towards the axis of the impellers to deflect the liquid inwardly as it enters the pump and reduce or ease the thrust as the liquid leaves the impellers.

Another object of the invention consists in providing means for maintaining the impel- 1ers in proper operative position relative to each other.

A still further object consists in connecting an air chamber with the casing so as to prevent the pounding or hammering of the liquid as it passes through the pump or when the liquid leaves the impellers.

Another object consists in associating a pump with a supply tank or the like and operatively connecting the pump with a storage receptacle and distributing instrumentalities whereby the pump may be selectively employed for either filling the tank or withdrawing the supply therefrom so as to uniformly distribute the liquid such as oil or the like on roads or other surfaces to bel covered or treated.

Referring to the drawings in which is dis,- closed several preferred embodiments of the invention- Figure 1 is a side elevation of the pump and its associated parts.

Figure 2 is a sectional view taken substantially along the line 2-2 of Figure 1.

Figure 3 is a sectional view taken substan- 50 tially along the line 3-3 of Figure 2.

Referring to the drawings in which like numerals indicate likeparts in the various views, 1() denotes a counter-balanced screw pump which essentially comprises a main body 11 to which is connected at one end an inlet head 12, in any suitable manner such as by the bolts 13. The opposite end of the body 11 preferably terminates in an upwardvly extending tubular portion 14, to which is secured by the bolts 15, an outlet head 16.

The main body 1.1 of the pump is provided with the intersecting axially arranged bores or channels 17 and 18 (Fig. 4), in which aremounted impeller shafts 19 and 20, respectively. These shafts have oppositely disposed helical screw threads 21 each of which closely lits within its respective bore and the space between the threads on the other shaft. In order to insure a liquid tight seal being formed by the threads and thus prevent the escape of liquid from the chambers formed therein, the shafts 19 and 2O have their threads formed in cross-section with oppositely disposed arcs or curves 22 and 23 (Fig. 4) on the periphery of the threads, andsimilarly formed arcs 24, 25 and 26 arranged on the sides thereof, so that as these shafts rotate in opposite directions the liquid will be effectively forced or rolled through the pump.

The inlet head 12 has mountedthereinthe stationary webs 27 and 28 (Fig. 5), each of which is provided with a longitudinal recess or socket 29 for receiving the adjacent reduced portions 30 and 31 of the impeller shafts 19 and 20 respectively. A bronze bushing or any other suitable bearing metal or a water lubricated rubber bearing 32 is suitably interposed between each of the shafts 3() and 31 and the adjacent wall of the socket 29, while the ends of the shafts 30 and 31 are further reduced as at 33 so as to fit within the adjacent section of a thrust bearing 34. In order to prevent the ,frictional engagement of the threads 21 adjusting bolts are arranged to extend through suitable openings in the webs 27 and 28, and abut against locking plates 36 which in turn engage rings37, that contact with the thrust 419 and 2O are rovided with reduced portions 38 and 39 ig. 2), which extend through openingsn 40 in theoutlet head 16. Each of the openings 40 is counterbored as at 41 so as to receive a packing 42 that is held in position by a gland nut 43 which is detachablyconnected toathe outlet head 16 by the threaded bolts'44. The reduced portions 38 and 39 of the impeller shafts have keyed thereon the intermeshing pinions 45 and 46 respectively, which are housed in a casing 47, that is connected to the end of the outlet head 16 by the bolts 48. The outer faces of the casing.47 is provided with the bosses 49 and 50 which act as a bearing for the reduced portions 38and 39 of the impeller shafts. The reduced portion 39of the lshaft 19 preferably extends beyond the housing 49 so as to be connected in any suitable manner to a driving mechanism not shown. The ends of the shafts may be supplied with a suitable lubricant through the grease cups 50 or withV ring oilers when the bushings for the shafts'are made of bronze or Babbitt metal. 1

It will be seen that upon rotation of the shaft 19 the piions 45 and 46 will cause simultaneous actuation of the impeilers 21 and thus draw in the liquid from the supply ipe 51 into the inlet head 12, and the main body 10 from where it is forced by the impellers through the outlet 16.

In order to reduce to a minimum the friction of the liquid as it enters the casing, the inlet ends .of the threads 21 have their faces inclined as at 52 (Fig. 2), toward the axis of the impeller shafts so that the liquid will be deflected inwardly when it issues from the supply pipe 51. The opposite ends of Athe threads 21 are similarly provided with inclined faces 52 so as to lessen the thrust as the liquid leaves the impellers. It will be seen that the parts are so constructed and arranged as to be readily dismantled for the purpose of inspection or repair. Additionally, the inlet supply 51 and the passage 1n the head 12 are in axial alignment with the bores in the main body 11 so as to provide a direct intake, which allows a free uninterrupted flow of the liquid as it is delivered to the pump. I The pump 10 and its associated parts may be stationarily mounted on any suitable sup- 'port or base by means of the brackets 53 that are preferably screwed to the body 11 bythe bolts 54.

In the.- modiiied form of the invj'ention shown in Figures 6 and .7 the pump casing 55 is'connected at one end to a downwardly extending inlet head 56 by the bolts 57, while its opposite extremity is preferabl formed with an enlarged portion 58 to whic is connected 'an air chamber 59- that communicates with the interior of the pump through a threaded nipple 60. The air chamber 59 is so positioned as toprevent the pounding or hammering of the liquid passing through-the pump.

An outlet head 61 and is provided 'with a'passage 63 whichldirectly communicates with the interior of the enlarged portion 58 of the pump to providev a channel formed to reduce to a minimum the friction of the liquid as it .passes through the pump. v

The interior of the casing 55 is also formed with a pair of axially extending bores in which are revolubly mounted a pair of impeller shafts 64 and 65 that are provided with interengaging double pitched threads y66 similar in construction and operation to the threads previously described.

The inlet head 56 hasa pair of longitudinal Iopenings 67 which are in alignment with the bores formed in the vchamber 55 and are 'is secured to the casing 5,5 adjacent therair chamber by the bolts 62 arranged to receive the ends of the shafts 64 r and 65. A bronze bushing 68 is interposed between each of the shafts and the adjacent wall of the opening 67. A packing 69 which is held in position by a gland nut 70 may be 'provided for preventing the escape of. liquid mit the axial adjustment of the shafts 64 and4 65. A gland nut 76 is threaded to each of the screws 75 to maintain the latter in a predetermined lock position.

The inlet head 56 is preferably provided with a vertical lubricating slot or opening 77 which communicates with the inlet supply passage so that the liquid as it delivers to the pump also acts as a vlubricant for the shafts 64 and 65. It will be seen that by reason of this particular construction', thaty when the pump is used for' distributing water, milk or other similar liquid that should be kept in a clean and sanitary condition, this liquid will serve as a lubricant thus avoiding the use of lubricating oil which not infrequently seeps past the bearings and mixes with the uid passing through the pump.

It will be observed that the inlet head 56 is so formed that the shafts 64` and 65 extend laterally to one side thereof, so'that the thrust bearings and adjusting screws are positioned outside of the pump and are not in the path of the liquid which permits these parts to be readily adjusted or inspected l without the dismantling of the ump.

The opposite ends of the sha s 64 and 65 extend through openingls in the lower portion of the outlet 61, in whic 'openings are mounted bronze bushings 77 or any other suitable bea-ring and also the packings which are maintained in positionI by glands 79. The glands 79 are maintained in position in substantiallyr the same manner as the acking glands 4 3 previously described. f owever,

these nuts may bethreaded in the same dir,ec tion in which their respective shafts 64 and 65 rotate so as to retain the desired compres- 81 whichare mounted in a housing 82 that is connected'- to the outlet head 61 by the bolts 83. One of the shafts 64 preferably extends beyond' the housing 82 and is connected to any suitable drive mechanism such as a motor or the like not shown.

)It will benoted that by reason of this particular -construction the impeller screws can be maintained in proper position with respect to each other vy means which are conveniently positioned outside of the casing. Moreover, the objectionable pounding or hammering of the liquid as it passes through the pump is eliminated due to the air chamber 59. y

It is to be understood that the form of the invention herein shown and described is merely "i illustrative of preferred embodimentsfand that such changes may be made as fall within the purview of one skilled in the art without departing from the spirit o f tllie invention and the scope of the appended c alm.

What I claim is:

A vpump of the class described comprising al casing having a main body, an inlet hea connected to one end of the body, the opposite endofsaid body terminating in an uppasses through the casing, a air of interengaging screw im ellers axia ly mounted in said casing, the s afts of saidA impellers extending through said inlet and outlet heads,

means forlubricating said shafts by the iuid passing through the casing, and means for maintaining said impellers in 'proper operative position relative to. each other.

In testimony whereof I have hereunto set my hand.

DANIEL D. LONG.

wardly projecting portion; an outlet head connected to said portion, means associated with said prolecting portion for preventing pounding or ammering of the liquid as it 

